Pleuroparenchymal fibroelastosis: a spectrum of histopathological and imaging phenotypes

Abstract

Pleuroparenchymal fibroelastosis (PPFE) is a rare condition characterised by predominantly upper lobe pleural and subjacent parenchymal fibrosis, the latter being intraalveolar with accompanying elastosis of the alveolar walls. The aim of this study was to review cases fulfilling published imaging and histological criteria, and identify any common clinical features that may suggest an underlying aetiology for a condition that has previously been regarded as idiopathic.Of 12 patients (seven females, median age 57 yrs), the presenting symptoms were shortness of breath (11 out of 12 patients) and dry cough (six out of 12 patients). Seven patients reported recurrent infections during the course of their disease. Five demonstrated nonspecific autoantibody positivity. Two patients had a family history of interstitial lung disease (ILD).High-resolution computed tomography features of lung disease remote from the pleuroparenchymal changes were present in six out of 12 patients (coexistent fibrosis, n55; bronchiectasis, n51). Of seven patients with tissue sampled from the lower lobes, four patients showed less intense PPFE changes (one with additional features of hypersensitivity pneumonitis) and three showed usual interstitial pneumonia.PPFE is a distinct clinicopathological entity, with clinical data suggesting a link to recurrent pulmonary infection. Genetic and autoimmune mechanisms may also contribute to the development of these changes. PPFE may also present with more diffuse involvement than previously reported, and coexist with different patterns of ILD.

Restrictive allograft syndrome post lung transplantation is characterized by pleuroparenchymal fibroelastosis

“…Our identification of pleuroparenchymal fibroelastosis in the setting of chronic lung allograft dysfunction, taken together with the recent report of pleuroparenchymal fibroelastosis following allogeneic bone marrow transplantation, 15 as well as the finding of auto-antibodies in some patients with pleuroparenchymal fibroelastosis, 14 could suggest a contributing immunologic mechanism. On the other hand, the presence of concurrent diffuse alveolar damage in a large proportion of restrictive allograft syndromepleuroparenchymal fibroelastosis cases may also suggest that pleuroparenchymal fibroelastosis represents a more non-specific late sequela of diffuse alveolar damage, which would be in keeping with the suggestion made by von der Thusen et al that pleuroparenchymal fibroelastosis in post-bone marrow transplant patients may represent a late complication of post-bone marrow transplant idiopathic pneumonia syndrome, which has a high mortality rate and is characterized clinically and radiologically by features consistent with diffuse alveolar damage.…”

“…15 If so, pleuroparenchymal fibroelastosis may represent a late complication of multiple and varied etiologic factors that result in acute lung injury/diffuse alveolar damage, including chemo/radiotherapy 7,10,11,15 and infections. 14 Finally, the finding of acute and/or organizing thromboemboli in our series raises the question of the role of vascular injury in the pathophysiology of pleuroparenchymal fibroelastosis. However, as thromboembolism may often be seen in the setting of diffuse alveolar damage and all instances of thromboemboli in this study were associated with diffuse alveolar damage, the significance of this finding to the development of pleuroparenchymal fibroelastosis is uncertain.…”

“…It is characterized radiologically by features suggestive of a chronic interstitial pneumonia with upper lobe predominance, and histologically by pleural fibrosis and parenchymal fibroelastosis in a predominantly subpleural distribution, with a sharp demarcation between fibroelastotic and unaffected lung parenchyma, and with the presence of fibroblastic foci at this interface. A limited number of cases with similar radiologic and pathologic features have also been reported, [8][9][10][11][12][13][14] including a very recent article by Reddy et al, 14 suggesting a broader spectrum of histopathologic findings.…”

“…Several cases and small series with similar radiologic and pathologic features have also been reported. [8][9][10][11][12][13][14] Radiologically, idiopathic pleuroparenchymal fibroelastosis has been characterized by pleural thickening associated with underlying parenchymal reticular abnormalities, architectural distortion and traction bronchiectasis in a mostly upper lobepredominant distribution. 7,10,11 Histologically, idiopathic pleuroparenchymal fibroelastosis is characterized by pronounced visceral pleural fibrosis associated with subpleural, 'intra-alveolar' fibrotic changes characterized by an admixture of elastic and fibrous tissue (fibroelastosis).…”

A Patient with Idiopathic Pleuroparenchymal Fibroelastosis Showing a Sustained Pulmonary Function due to Treatment with Pirfenidone

“…IPPFE comprises dense established intra-alveolar fibrosis, with the alveolar walls in these areas showing prominent elastosis, and dense fibrous thickening of the visceral subpleura; these changes have a striking upper-zone predominance (9). Marked apical pleural thickening associated with superior hilar retraction is present on chest X-ray, and HRCT shows pleural thickening, fibrosis, architectural distortion, traction bronchiectasis, and honeycomb lung (7).…”